$$25\mathrm{.}00$ per hundredweight for direct shipment to the customer for shipments weighing $1,000$ to $4,999$ pounds; $$23\mathrm{.}00$ per hundredweight for orders weighing $5,000$ to $9,999$ pounds; and $$21\mathrm{.}00$ for shipments weighing between $10,000$ and $15,000$ pounds. Alternatively, the carrier's rate for shipments weighing more than $20,000$ pounds is $$18\mathrm{.}00$ per hundredweight. However, if the orders are combined into one consolidated shipment, the carrier will charge $$290$ for each stop it is required to make.

a$.$ Calculate the total cost with or without consolidated shipment charge.

b$.$ Should Jones consolidate the three shipments?